package vip.zhenzicheng.nettybasic.serializable.msgpack;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.LengthFieldBasedFrameDecoder;

import java.net.InetSocketAddress;

/**
 * @author zhenzicheng
 * @date 2022-06-27 15:55
 */
public class ServerMsgPackEcho {

  public static final int PORT = 9995;

  public static void main(String[] args) throws InterruptedException {
    ServerMsgPackEcho serverMsgPackEcho = new ServerMsgPackEcho();
    System.out.println("服务器即将启动");
    serverMsgPackEcho.start();
  }

  public void start() throws InterruptedException {
    final MsgPackServerHandler serverHandler = new MsgPackServerHandler();
    EventLoopGroup group = new NioEventLoopGroup();/*线程组*/

    try {
      ServerBootstrap b = new ServerBootstrap();/*服务端启动必须*/
      b.group(group)/*将线程组传入*/
          .channel(NioServerSocketChannel.class)/*指定使用NIO进行网络传输*/
          .localAddress(new InetSocketAddress(PORT))/*指定服务器监听端口*/
          /*服务端每接收到一个连接请求，就会新启一个socket通信，也就是channel，
          所以下面这段代码的作用就是为这个子channel增加handle*/
          .childHandler(new ChannelInitializerImp());
      ChannelFuture f = b.bind().sync();/*异步绑定到服务器，sync()会阻塞直到完成*/
      System.out.println("服务器启动完成，等待客户端的连接和数据.....");
      f.channel().closeFuture().sync();/*阻塞直到服务器的channel关闭*/
    } finally {
      group.shutdownGracefully().sync();/*优雅关闭线程组*/
    }
  }

  private static class ChannelInitializerImp extends ChannelInitializer<Channel> {

    @Override
    protected void initChannel(Channel ch) throws Exception {
      ch.pipeline().addLast(new LengthFieldBasedFrameDecoder(65535,
          0, 2, 0,
          2));
      ch.pipeline().addLast(new MsgPackDecoder());
      ch.pipeline().addLast(new MsgPackServerHandler());
    }
  }

}
